To study the trophic influences on the corneal epithelium that govern the early phases of wound healing in rabbits, we will measure mitotic rate, glycogen utilization, cyclic AMP and cyclic GMP and sliding of the epithelium after trauma to the cornea. We will use ganglionectomy to study sympathomimetic phenomena in the cornea following release of norepinephrine from adrenergic nerves, which will be localized by fluorescent histochemical techniques. The presence and localization of alpha and beta receptors in the corneal epithelium will be determined using specific tritium labeled ligands. We will study the involvement of prostaglandins in the early phases of wound healing in the cornea, as well as alteration of the system using phosphodiesterase inhibitors, adenyl cyclase stimulators and other pertinent drugs. The physiological responses to cyclic AMP will be investigated by studying calcium movements and changes in subcellular components, such as microtubules and microfilaments.